package com.example.skycode6.dao;

import com.example.skycode6.bean.NewsBean;
import com.example.skycode6.util.DBConnection;
import com.example.skycode6.util.Time;

import java.sql.*;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

public class NewsDao {
    DBConnection DBConn = new DBConnection();

    // todo 完成增删改查功能
    public List<NewsBean> getList(int page) {
        Connection conn = DBConn.getConn();
        String sql = "select * from news limit " + (page - 1) * 10 + ",10";
        List<NewsBean> list = new ArrayList<>();
        try {
            Statement stmt = conn.createStatement();
            ResultSet rs = stmt.executeQuery(sql);
            while (rs.next()) {
                NewsBean newsBean = new NewsBean();
                newsBean.setNewsID(rs.getInt("NewsID"));
                newsBean.setNewsTitle(rs.getString("NewsTitle"));
                newsBean.setNewsContent(rs.getString("NewsContent"));
                newsBean.setNewsTime(Time.getDateTime());
                newsBean.setAdminName(rs.getString("AdminName"));
                list.add(newsBean);
            }
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }
        return list;
    }

    /**
     * @param newsBean 传入要更新的新闻对象，必须包含新闻id值
     * @return 受影响的行数
     */
    public int update(NewsBean newsBean) {
        Connection conn = DBConn.getConn();
        if (newsBean.getNewsID() > 0) {
            try {
                Statement stmt = conn.createStatement();
                String sql = "update news set NewsTitle='" + newsBean.getNewsTitle() + "'"
                        + ",NewsContent='" + newsBean.getNewsContent() + "'"
                        + ",NewsTime='" + Time.getDateTime() + "'"//更新时使用当前系统时间
                        + ",AdminName='" + "假管理员" + "'" //todo使用添加的管理员名称
                        + " where NewsID=" + newsBean.getNewsID();
                return stmt.executeUpdate(sql);
            } catch (SQLException e) {
                e.printStackTrace();
            }
            return 0;
        }
        return 0;
    }

    public int add(NewsBean newsBeaan) {
        Connection conn = DBConn.getConn();
        try {// 使用预处理执行插入
            String sql = "insert into news(NewsTitle,NewsContent,NewsTime,AdminName) values(?,?,?,?)";
            PreparedStatement pmst = conn.prepareStatement(sql);
            pmst.setString(1, newsBeaan.getNewsTitle());
            pmst.setString(2, newsBeaan.getNewsContent());
            pmst.setString(3, (new Date()).toString());
            pmst.setString(4, "临时管理员");//将第一个参数设置为标题内容
            return pmst.executeUpdate();
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return 0;
    }

    /**
     * 删除功能
     */
    public int deleteNewsById(int newsID) {
        Connection conn = DBConn.getConn();
        try {
            String sql = "delete from news where NewsID=?";
            PreparedStatement pmst = conn.prepareStatement(sql);
            pmst.setInt(1, newsID);
            return pmst.executeUpdate();
        } catch (SQLException e) {

        }
        return 0;
    }

    public int countPage() {
        Connection conn = DBConn.getConn();
        String sql = "select count(*) from news";
        try {
            Statement statement = conn.createStatement();
            ResultSet rs = statement.executeQuery(sql);// 获取查询结果集
            if (rs.next()) {
               return (rs.getInt(1)/10) +1;
            }
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }
        return 0;
    }
}